fix slot fallback update parent

test/runtime/samples/component-slot-fallback-5/IconA.svelte

@@ -0,0 +1 @@
+Icon A

test/runtime/samples/component-slot-fallback-5/IconB.svelte

@@ -0,0 +1 @@
+Icon B

test/runtime/samples/component-slot-fallback-5/Inner.svelte

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+<script>
+  import IconA from './IconA.svelte';
+  import IconB from './IconB.svelte';
+
+  let variable = false;
+</script>
+
+<button on:click={() => variable = !variable}>Click Me</button>
+<div>
+  <slot>
+    <svelte:component this={variable ? IconA : IconB} />
+  </slot>
+</div>

test/runtime/samples/component-slot-fallback-5/_config.js

@@ -0,0 +1,31 @@
+export default {
+	html: `
+	<button>Click Me</button>
+	<div>Icon B</div>
+	`,
+
+	async test({ assert, target, window }) {
+		const btn = target.querySelector("button");
+		const clickEvent = new window.MouseEvent("click");
+
+		await btn.dispatchEvent(clickEvent);
+
+		assert.htmlEqual(
+			target.innerHTML,
+			`
+			<button>Click Me</button>
+			<div>Icon A</div>
+			`
+		);
+
+		await btn.dispatchEvent(clickEvent);
+
+		assert.htmlEqual(
+			target.innerHTML,
+			`
+			<button>Click Me</button>
+			<div>Icon B</div>
+			`
+		);
+	}
+};

test/runtime/samples/component-slot-fallback-5/main.svelte

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+<script>
+	import Inner from "./Inner.svelte";
+</script>
+
+<Inner></Inner>